(1).IntroductionThe effect of thermochemotherapy on hamster oral squamouscell carcinomas (O-1N) were studied in their primaiy sites and in their cervical lymph node metastasis.(2).Materials and MethodsGolden hamster in which O-1N was transplanted into the cheek pouch were divided into 4 group: a hyperthermia group(HG) subjected to radiofrequency(RF) hypothermia at 43℃ for 40 minutes twice a week, a chemotherapy group(CG) in which the docetaxel was administered twice a week (10mg/kg i.p.), a thermochemotherapy group(TCG) in which docetaxel was given immediately before hyperthermia, and an untreated group(UG). When the buccal tumor reached 7mm in diameter, it was heated with a 13.56 MHz RF capacitive hyperthermia system. Intratumoral temperature was measured continuously by the C-C thermocouple thermometer. The tumor volume was calculated, primary tumor and cervical lymph nodes were excised three and four weeks after treatment, respectively, and were examined histologically.(3).ResultsThe primary tumor size was inhibited after treatment in the CG, it was decreased in the HG and TCG. Complete disappearance of tumor cells was confirmed histologically in 0 of 19 animals (0%) in the CG,3 of 16 animals (18.5%) in the HG,and 11 of 15 animals (73.3%) in the TCG. The incidence of lymph node metastasis was 42.1%(8 of 19 animals) in the CG,6.3%(1 of 16 animals) in the HG,and 13.3% (2 of 15 animals) in the TCG, compared with 88.9% (8 of 9 animals) in the UG. The histological pattern of lymph node metasitasis in the all group were confirmed within the lymph node capsule. In conclusion, the anti-tumor effect was enhanced when hyperthermia was combined with chemotherapy by docetaxel, both hyperthermia and thermochemotherapy inhibited lymph node metastasis.